Demodulator and multi-chip module for a multi-mode receiver and method therefor

ABSTRACT

In one form, a multi-chip module for a multi-mode receiver includes an MCM substrate and first and second demodulator die. The MCM substrate has first and second satellite input ports, first and second terrestrial/cable input ports, and first and second transport stream ports. The first demodulator die has a satellite port coupled to the first satellite input port of the MCM substrate, a terrestrial/cable port coupled to the first terrestrial/cable input port of the MCM substrate, and first and second transport stream ports coupled to the first and second transport stream ports of the MCM substrate. The second demodulator die has a satellite port coupled to the second satellite input port of the MCM substrate, a terrestrial/cable port coupled to the second terrestrial/cable input port of the MCM substrate, and first and second transport stream ports coupled to the first and second transport stream ports of the MCM substrate.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to receivers, and moreparticularly to multi-mode receivers such as television receiverscapable of receiving and demodulating different input signal streams.

BACKGROUND

Certain television receivers support multiple simultaneous channelreception and demodulation of signals from different types of signalsources. For example, a television may support both satellite andterrestrial/cable input signal sources, and the user may desire to watcha satellite channel while recording a terrestrial/cable channel or viceversa. This diversity of input signal sources makes it difficult todesign cost-effective receivers that support all desired modes ofoperation. For example, in a receiver with two or more televisiondemodulators, the outputs from the demodulators may need to bemultiplexed or rerouted to different video decoders based on the desiredmode of operation. This selection of features has necessitated costlycircuits such as discrete crossbar switches to support all desiredfunctions. While modern integrated circuit manufacturing technologieshave resulted in significant component cost reduction, further costreduction is desirable while maintaining all desired operational modes.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be better understood, and its numerousfeatures and advantages made apparent to those skilled in the art byreferencing the accompanying drawings, in which:

FIG. 1 illustrates in block diagram form a multi-mode receiver known inthe prior art;

FIG. 2 illustrates in block diagram form a multi-mode receiver accordingto one embodiment;

FIG. 3 illustrates a perspective view of a multi-chip moduleimplementing the multi-mode receiver of FIG. 2;

FIG. 4 illustrates in block diagram form a demodulator using a singledemodulator die to form a low-cost receiver;

FIG. 5 illustrates in block diagram form a demodulator using multipledemodulator die to form a high-function receiver;

FIG. 6 illustrates in block diagram form a demodulator that can be usedas one of the demodulators of any of FIGS. 2-5;

FIG. 7 illustrates in block diagram form a demodulator like thedemodulator of FIG. 6 illustrating further details of the collisiondetector; and

FIG. 8 illustrates in block diagram form a receiver using thedemodulator die of FIGS. 6 and 7 to support a channel bonding mode.

The use of the same reference symbols in different drawings indicatessimilar or identical items. Unless otherwise noted, the word “coupled”and its associated verb forms include both direct connection andindirect electrical connection by means known in the art, and unlessotherwise noted any description of direct connection implies alternateembodiments using suitable forms of indirect electrical connection aswell.

DETAILED DESCRIPTION

In one form, a multi-chip module for a multi-mode receiver includes anMCM substrate and first and second demodulator die. The MCM substratehas first and second satellite input ports, first and secondterrestrial/cable input ports, and first and second transport streamports. The first demodulator die has a satellite port coupled to thefirst satellite input port of the MCM substrate, a terrestrial/cableport coupled to the first terrestrial/cable input port of the MCMsubstrate, and first and second transport stream ports coupled to thefirst and second transport stream ports of the MCM substrate. The seconddemodulator die has a satellite port coupled to the second satelliteinput port of the MCM substrate, a terrestrial/cable port coupled to thesecond terrestrial/cable input port of the MCM substrate, and first andsecond transport stream ports coupled to the first and second transportstream ports of the MCM substrate. By connecting transport stream portsof the two demodulator die in common to corresponding transport streamports of the MCM substrate, the MCM can be made more cheaply byeliminating the need for a discrete crossbar switch.

In another form, a demodulator for a multi-mode receiver includes afirst input port, a second input port, a first transport stream port, asecond transport stream port, a demodulator core, and a switchingcircuit. The demodulator core is responsive to an input from a selectedone of the first input port and the second input port for providing afirst transport stream signal to an output thereof. The switchingcircuit is responsive to a first mode for coupling the output of thedemodulator core to a selected one of the first and second transportstream ports. In one configuration, the demodulator can be used byitself to form a low-cost receiver by connecting only one of itstransport stream output ports to an integrated circuit package or MCM.In another configuration, the demodulator can be combined with one ormore similar demodulators in a multi-chip module or other collection ofcircuits to form a high function receiver for applications such ashigh-end televisions and set-top boxes.

In yet another form, a method includes receiving a first input signal ona first input port of a first demodulator die, receiving a second inputsignal on a second input port of the first demodulator die, demodulatinga selected one of the first input signal and the second input signal toprovide a first demodulated output signal, switching the firstdemodulated output signal to a first transport stream port in responseto a first mode of operation, and switching the first demodulated outputsignal to a second transport stream port in response to a second mode ofoperation. This method can be used, for example, to implement atelevision receiver which receives both satellite and terrestrial/cablesignals to support multiple modes of operation.

FIG. 1 illustrates in block diagram form a multi-mode receiver 100 knownin the prior art. Multi-mode receiver 100 includes generally a tunerportion 102, a crossbar switch 130 labeled “XBAR”, a decoder 140 capableof decoding a Motion Picture Experts Group (MPEG) signal stream labeled“MPEG DECODER”, and a decoder 150 labeled “SATELLITE CONDITIONAL ACCESSMODULE”.

Tuner portion 102 includes four tuners 106, 108, 112, and 114 and twodemodulators 116 and 118. Tuner 106 is a satellite tuner labeled “ST”having an input adapted to be coupled to a first type of signal sourcesuch as a satellite radio dish antenna, and an output. Tuner 108 is asatellite tuner (ST) having an input adapted to be coupled to the firsttype of signal source, and an output. Tuner 112 is a television tunerlabeled “TV” having an input adapted to be coupled to a second type ofsignal source such as a television antenna, cable, and the like, and anoutput. Tuner 114 is a television tuner (TV) having an input adapted tobe coupled to the second type of signal source, and an output.

Demodulator 116 has a first input connected to the output of tuner 106,a second input connected to the output of tuner 112, a control input forreceiving a control signal labeled “CTRL”, and an output. Demodulator118 has a first input connected to the output of tuner 108, a secondinput connected to the output of tuner 114, a control input forreceiving signal CTRL, and an output.

Crossbar switch 130 has a first input connected to the output ofdemodulator 116, a second input coupled to the output of demodulator118, and first and second outputs. Decoder 140 has an input connected tothe first output of crossbar switch 130, and an output (not shown inFIG. 1). Decoder 150 has an input connected to the second output ofcrossbar switch 130, and an output (not shown in FIG. 1).

Note that various signals are depicted herein as single signal lines forsimplicity but actually include multiple individual signal lines. Forexample, the satellite and terrestrial or cable inputs are usuallydifferential signals, and the outputs of demodulators 116 and 118 aretransport stream signals defined by the MPEG standard and include twelvedigital signal lines. Moreover the CTRL signal is actually a set ofcontrol signals that are different for each demodulator.

In operation, multi-mode receiver 100 is useful in applications such asmulti-tuner televisions or set-top boxes to provide a variety ofuser-defined functions. For example if a user wants to record asatellite program while watching a cable program, then a host (not shownin FIG. 1) would provide the CTRL signal in a state to enabledemodulator 116 to select its first input and demodulator 118 to selectits second input. The host would also configure crossbar switch 130 toswitch the output of demodulator 116 to decoder 150 to decrypt the videosignal stream and decode the MPEG data, while switching the output ofdemodulator 118 to decoder 140 to decode the terrestrial or cable-basedMPEG data stream. By including four tuners and providing the output ofone cable tuner and one terrestrial/cable tuner to each demodulator,multi-mode receiver 100 provides the user with significant flexibilityof functions.

Moreover, the components in tuner portion 102 can take advantage ofmodern integrated circuit technology to provide a low cost and flexibleimplementation. For example, each demodulator can be formed using aseparate integrated circuit die that can be combined with anothersimilar or identical die for a multi-tuner implementation.Alternatively, the same demodulator die can be used as the soledemodulator for a low-cost implementation. Moreover, the two demodulatordies can be designed using low-voltage complementarymetal-oxide-semiconductor (CMOS) manufacturing processes and can becombined in a multi-chip module for further cost reduction. While thesetechniques enable low-cost designs, further cost reduction is desirablewhile retaining the same functionality.

FIG. 2 illustrates in block diagram form a multi-mode receiver 200according to one embodiment. Multi-mode receiver 200 includes generallya satellite tuner section 210, a terrestrial/cable tuner section 220, amulti-chip module (MCM) 240, an MPEG decoder 260, and a satelliteconditional access module 270.

Satellite tuner section 210 includes a satellite tuner 212 labeled “STUNER A” and a satellite tuner 214 labeled “S TUNER B”. Satellite tuner212 has an input for receiving a radio frequency (RF) input signal froma satellite labeled “S_RF_A”, and an output. Satellite tuner 214 has aninput for receiving an RF input signal from a satellite labeled“S_RF_B”, and an output.

Terrestrial/cable tuner section 220 includes a splitter 222, aterrestrial/cable tuner 224 labeled “T/C TUNER A”, and aterrestrial/cable tuner 224 labeled “T/C TUNER B”. Splitter 222 has aninput adapted to be connected to, for example, a residential cableaccess point, and first and second outputs. Terrestrial/cable tuner 224has an input connected to the first output of splitter 222, and anoutput. Terrestrial/cable tuner 226 has an input connected to the secondoutput of splitter 222, and an output.

MCM 240 includes a first demodulator die 247 and a second demodulatordie 248, and has a first satellite input port 241 connected to theoutput of satellite tuner 212 for receiving a signal labeled“S_IN_(—)1”, a second satellite input port 242 connected to the outputof tuner 214 for receiving a signal labeled “S_IN_(—)2”, a firstterrestrial/cable input port 243 connected to the output ofterrestrial/cable tuner 224 for receiving a signal labeled “TC_IN_(—)1”,a second terrestrial/cable input port 244 connected to the output oftuner 226 for receiving a signal labeled “TC_IN_(—)2”, a fifth MCMterminal 245 for providing a transport stream signal labeled “TS_X”, anda sixth terminal 246 for providing a transport stream signal labeled“TS_Y”. MCM 240 includes a first demodulator die 247 and a seconddemodulator die 248. Demodulator die 247 has a satellite input terminallabeled “S_IN” connected to MCM terminal 241, a terrestrial/cableterminal labeled “T/C_IN” connected to first terrestrial/cable inputport 243, a first transport stream output terminal connected to firsttransport stream port 245, and a second transport stream output terminalconnected to second transport stream port 246. Demodulator die 248 has asatellite input terminal also labeled “S_IN” connected to secondsatellite input port 242, a terrestrial/cable terminal also labeled“T/C_IN” connected to MCM terminal 244, a first transport stream outputterminal connected to first transport stream port 245, and a secondtransport stream output terminal connected to second transport streamport 246.

MPEG decoder 260 has an input terminal connected to first transportstream port 245, and an output (not shown in FIG. 2). Satelliteconditional access module 270 has an input terminal connected to secondtransport stream port 246, and an output (not shown in FIG. 2).

Unlike multi-mode receiver 100 of FIG. 1, multi-mode receiver 200eliminates the need for a discrete crossbar switch, which reducesoverall cost by reducing printed circuit board space and chip count. Aswill be described in greater detail below, the multi-mode receiver 200uses demodulator dies 247 and 248 and distributes the output signalswitching function between the two. Thus corresponding outputs of eachdie can be connected to common MCM terminals while still allowing thehost to configure multi-mode receiver 200 flexibly during operation.Moreover, each die can be used either in a low cost receiver with asingle demodulator, or a high function receiver with two or moredemodulators in a common MCM. Each demodulator die includes both ademodulator core and a switching circuit and supports additionalfunctions to provide further flexibility. One of these functions is afailsafe mechanism to allow the demodulators to independently detect andprevent the harmful effects of a collision if both dies try to drive asingle transport stream output. Another function is the ability toconnect the dies in a way to perform channel bonding. These additionalcapabilities will be described further below.

Note that while FIG. 2 shows an MCM with two demodulator die, thisapproach can be extended to an arbitrary number of demodulator die forreceiver applications with even higher functions. Also while FIG. 2 hasbeen described with respect to the MPEG transport stream, any other datatransport stream protocol may be used as well, such as the GenericStream Encapsulated (GSE) protocol.

FIG. 3 illustrates a perspective view of an MCM 300 implementing themulti-mode receiver of FIG. 2. MCM 300 includes an MCM substrate 310, afirst demodulator die 320, a second demodulator die 330, and anencapsulant 340. MCM substrate 310 is a substrate providing a set oflanding pads for wire bonding to corresponding chip signal pads, and aset of corresponding terminals such as solder balls in the case of ballgrid array (BGA) packaging or terminals flush with the underside of MCMsubstrate 310.

As shown in FIG. 3, substrate 310 includes a set of landing pads on thetop side of MCM substrate 310 corresponding transport streams X and Yincluding as a set of representative landing pads shown in FIG. 3. TABLEI shows the complete list of MPEG transport stream signals supported byMCM 300:

TABLE I MCM Pin Name Transport Stream Port Function TS_SYNC_X XSynchronization signal TS_VAL_X X Valid signal TS_CLK_X X Clock signalTS_DATA<7:0>_X X Data TS_ERR_X X Error signal TS_SYNC_Y YSynchronization signal TS_VAL_Y Y Valid signal TS_CLK_Y Y Clock signalTS_DATA<7:0>_Y Y Data TS_ERR_Y Y Error signal

In an exemplary embodiment, MCM substrate 310 is a lead frame in whichfirst demodulator die 320 and second demodulator die 330 overlie apaddle, and in which encapsulant 340 is a plastic. First demodulator die320 is attached to the paddle of MCM substrate 310 using silver filledepoxy for mechanical adhesion to the paddle. Second demodulator die 330is attached to first demodulator die 320 using a nonconductive adhesivefilm (not visible in FIG. 3) of sufficient height to allow the bondwires to extend through the film (wire-on-film) from bonding pads onfirst demodulator die 320 to corresponding landing pads on MCM substrate310 without encroachment.

In other embodiments, MCM 300 can be implemented with other well knownpackaging technologies, such as ceramic, micro-BGA, plastic QFN and thelike.

FIG. 4 illustrates in block diagram form a demodulator 400 using asingle demodulator die 420 to form a low-cost receiver. Demodulator 400has a first input port for connecting to a satellite receiver and asecond input port for connecting to a terrestrial/cable receiver,neither of which is specifically shown in FIG. 4. Demodulator 400provides only a single transport stream output to a transport streamport 430 and includes only a single demodulator die 420 mounted on anintegrated circuit substrate 410. Demodulator die 420 intermixes bondpads of both the TS_X and TS_Y ports to preserve a regular placement ofbond wires even when supporting only a single transport stream output.The bond pads of demodulator die 420 are wire-bonded to landing padscorresponding to the single transport stream output port.

FIG. 5 illustrates in block diagram form a demodulator 500 usingmultiple demodulator die to form a high-function receiver. Demodulator500 has a first input port for connecting to a satellite receiver and asecond input port for connecting to a terrestrial/cable receiver,neither of which is specifically shown in FIG. 5. Demodulator 500provides dual transport stream outputs to a corresponding output port540 and includes a first demodulator die 520 and a second demodulatordie 530 mounted on an integrated circuit substrate 510. Firstdemodulator die 520 intermixes bond pads of both the TS_X and TS_Y portsto preserve a regular placement of bond wires even when supporting onlya single transport stream output. The bond pads of first demodulator die520 are wire-bonded to landing pads corresponding to the two transportstream output ports. Likewise, the bond pads of second demodulator die530 are wire-bonded to landing pads corresponding to the two transportstream output ports.

FIG. 6 illustrates in block diagram form a demodulator 600 that can beused as one of the demodulators of any of FIGS. 2-5. Demodulator 600includes a demodulator core 610, a switching circuit 620, a firsttransport stream port 630, and a second transport stream port 640.Demodulator core 610 includes a first input port 611 for receiving asatellite input signal labeled “S_IN”, a second input terminal 612 forreceiving a terrestrial/cable input labeled “T/C_IN”, a serialinput/output terminal 613 for transmitting signals labeled “SERIAL I/O”,a serial port 614, a set of configuration registers 616, and a collisiondetector 618. Serial port 614 controls the serial communication over theSERIAL I/O signals with an external host to receive and storeconfiguration information in configuration registers 616. Theconfiguration information includes the selection of an input mode whichdetermines whether demodulator core 610 demodulates the S_IN_signal orthe T/C_IN signal, and the selection of transport stream port X,transport stream port Y, or both transport stream port X and transportstream port Y. According to this latter selected mode, demodulator core610 activates a signal labeled “OE_X” to select the X port, “OE_Y” toselect the Y port, or both OE_X and OE_Y to select both transport streamports X and Y. Collision detector 618 has first and second inputs, andoutputs (not specifically shown in FIG. 6) for providing a collisionsignal.

Switching circuit 620 includes a set of input and output buffers foreach signal of the transport stream port as described above in TABLE I,of which a representative one transport stream port data is shown inFIG. 6. Thus switching circuit 620 includes for this one representativetransport stream port buffers 622, 624, 626, and 628. Buffer 622 is anoutput buffer and has an input connected to the output of demodulatorcore 610, an output, and a control input for receiving signal labeled“OE_X”. Buffer 624 is a readback buffer and has an input connected tothe output of buffer 622, and an output connected to the first input ofcollision detector 618. Buffer 626 is an output buffer and has an inputconnected to the output of demodulator core 610, an output, and acontrol input for receiving a signal labeled “OE_Y”. Buffer 628 is areadback buffer and has an input connected to the output of buffer 626,and an output connected to the second input of collision detector 618.

First transport stream port 630 includes, for example, twelve terminalseach comprising a bonding pad, in which FIG. 6 illustrates arepresentative bonding pad 632 connected to the output of buffer 622 andto the input of buffer 624. Second transport stream port 640 includes,for example, twelve terminals each comprising a bonding pad, in whichFIG. 6 illustrates a representative bonding pad 642 connected to theoutput of buffer 626 and to the input of buffer 628.

Demodulator 600 includes an additional collision detection function thatallows demodulator 600 to detect a collision and to take appropriateactions. If operating properly, software running on the host shouldconfigure no more than one of the two or more demodulators to driveoutput signals on any respective transport stream port. Thus the hostsends serial data on serial port 614 to enable the appropriate one orones of buffers 622 and 626, while keeping the other one or ones in highimpedance mode. However if the host hardware or software malfunctions orthe data transmitted to serial port 614 to configure the output buffersmalfunctions, then collision detector 618 and readback buffers 624 and628 provide a failsafe mechanism to disable operation when a collisionis detected. For example, suppose that the MCM includes two demodulatordie, and both of the two are erroneously configured to drive transportstream port 1 at the same time. In this case, a collision detector 618on one of the two die will eventually detect a mismatch between thelogic state intended to be driven and the logic state actually presenton the bus. For example if the first demodulator attempts to drive alogic low value while the second demodulator attempts to drive a highvalue, the value on the commonly connected transport stream port willassume an intermediate state which one collision detector 618 sees as amismatch. The demodulator that sees the mismatch will immediatelydisable all output buffers on the corresponding demodulator die andsignal an interrupt to the host. Thus the collision detection mechanismprevents integrated circuit damage by quickly disabling one of thedemodulators and by signaling the host so the host can diagnose thecause of the collision.

FIG. 7 illustrates in block diagram form a demodulator 700 likedemodulator 600 of FIG. 6 illustrating further details of the collisiondetector. Demodulator 700 includes switching circuit 620, firsttransport stream port 630, and second transport stream port 640 aspreviously illustrated in FIG. 6, and a collision detector 710.Collision detector 710 includes a flip-flop 712, an exclusive OR gate714, a flip-flop 716, a flip-flop 722, an exclusive OR gate 724, aflip-flop 726, a flip-flop 730, a collision detection state machine 750,and a clock generation circuit 760. Flip-flop 712 is a D-type flip-flophaving a D input connected to the output of buffer 624, a clock inputfor receiving a signal labeled “ TS_CLK”, a Q output, and an unused Qoutput. Exclusive OR gate 714 has a first input connected to the Qoutput of flip-flop 712, a second input, and an output. Flip-flop 716 isa D-type flip-flop having a D input connected to the output of exclusiveOR gate 714, a clock input for receiving a signal labeled “TS_CLK”, a Qoutput, and an unused Q output. Flip-flop 722 is a D-type flip-flophaving a D input connected to the output of buffer 628, a clock inputfor receiving the TS_CLK signal, a Q output, and an unused Q output.Exclusive OR gate 724 has a first input connected to the Q output offlip-flop 722, a second input, and an output. Flip-flop 726 is a D-typeflip-flop having a D input connected to the output of exclusive OR gate724, a clock input for receiving the TS_CLK signal, a Q output, and anunused Q output. Flip-flop 730 is a D-type flip-flop having a D inputfor receiving an output data signal, a clock input for receiving asignal labeled “TS_CLK_D”, a Q output connected to the second inputs ofexclusive OR gates 714 and 724 and to the inputs of buffers 622 and 626,and an unused Q output.

Collision detection state machine 750 has a first input connected to theQ output of flip-flop 716, a second input connected to the Q output offlip-flop 726, a first output for providing an interrupt signal labeled“INT”, and a second output for providing a control signal labeled“DISABLE OUTPUT”. Clock generation circuit 760 includes inverters 762and 764. Inverter 762 has an input for receiving the TS_CLK signal, andan output for providing the TS_CLK signal. Inverter 762 has an inputconnected to the output of inverter 762, and an output for providing theTS_CLK_D signal.

Flip-flops 712 and 722 capture the values on transport stream ports 630and 640 through readback buffers 624 and 628, respectively coincidentwith the rising edge of the TS_CLK signal. Meanwhile, flip-flop 730functions to capture the output data coincident with the rising edge ofthe TS_CLK_D signal. Thus, exclusive OR gates 714 and 724 compare theoutgoing data with the readback data at a point in time when they areboth stable. The outputs of exclusive OR gates 714 and 724 are a logichigh when the outgoing data is dissimilar to the readback data, whichindicates a collision. The outputs of the exclusive OR gates 714 and 724are then captured one-half clock cycle later in flip-flops 716 and 726,which are active on the rising edge of the TS_CLK signal.

In response to an activation of the Q output of either flip-flop 716 orflip-flop 726, collision detection state machine 750 detects acollision. It takes two actions in response. First, it activates theDISABLE OUTPUT signal. Control circuitry in demodulator 700 activatessignals OE_X and OE_Y in partial dependence on the DISABLE OUTPUT signalsuch that in response to an activation of the DISABLE OUTPUT signal, thecontrol circuitry keeps the OE_X and OE_Y signals inactive, which inturn prevents buffers 622 and 626 from driving transport stream ports630 and 640, respectively. These signals remain inactive untildemodulator 700 is reset by the host.

The second action is that collision detection state machine 750activates the INT signal to the host. In response, the host interruptvector may provide a mechanism to read the registers of the demodulatordie through their serial I/O ports and determine which port of whichparticular demodulator die was erroneously set, and take any furthercorrective or reporting actions it deems appropriate.

As with FIG. 6 above, the signals in demodulator 700 are merelyrepresentative of one data signal and demodulator 700 will includesimilar circuitry for each transport stream data signal such thatcollision detection state machine 750 is able to detect a collision onany data signal. In this way, it will detect the collision early, evenwhen some or maybe most of the data is coincident between the two ormore demodulators.

Providing readback buffers such as buffers 624 and 628 for eachtransport stream output pin allows an additional capability which willnow be described.

FIG. 8 illustrates in block diagram form a receiver 800 using thedemodulator die of FIGS. 6 and 7 to support a channel bonding mode.Receiver 800 includes a first MCM 810 and a second MCM 820. First MCM810 includes a demodulator die 812 and a demodulator die 814 whose bondpads are wire bonded to the MCM substrate as shown in FIG. 5 above.First MCM 810 has a TS_X output port illustrated by a representative MCMterminal 816 and a TS_Y port illustrated by a representative MCMterminal 818. Each of demodulator die 812 and demodulator die 814includes both a TS_X port and a TS_Y port wire bonded to the TS_X andTS_Y ports, respectively, of first MCM 810. As shown in FIG. 8, the hosthas configured the TS_X port of demodulator die 812 to be active, whilethe TS_Y port of demodulator die 812 is inactive. The host alsoconfigures the TS_X port of demodulator die 814 to be inactive, whilethe TS_Y port of demodulator die 812 is active. However, the hostconfigures demodulator die 814 to use the TS_X port as an input portusing the available readback buffers. Thus, the availability of readbackbuffers allows first MCM 810 to implement a function known as channelbonding in which the TS_X output of demodulator die 812 is combined withthe output of the demodulator core of demodulator die 814 to form abonded channel signal which is then provided to the TS_Y port of MCM810.

MCM 820 provides further channel bonding. Second MCM 820 includes ademodulator die 822 and a demodulator die 824 whose bond pads are wirebonded to the MCM substrate as shown in FIG. 5 above. Second MCM 820 hasa TS_X2 port illustrated by a representative MCM terminal 826 and aTS_Y2 port illustrated by a representative MCM terminal 828. Each ofdemodulator die 822 and demodulator die 824 includes both a TS_X portand a TS_Y port wire bonded to the TS_X2 and TS_Y2 ports, respectively,of second MCM 820. As shown in FIG. 8, the host has configured the TS_Xport of demodulator die 822 to be inactive, and the TS_Y port ofdemodulator die 822 to be active. In the example of FIG. 8 in whichthree channels are bonded, the host also configures both the TS_X portand the TS_Y port of demodulator die 824 to be inactive. The hostconfigures demodulator die 824 to use the TS_X port as an input portusing the available readback buffers, and second MCM 820 extends thechannel bonding to three channels.

The above-disclosed subject matter is to be considered illustrative, andnot restrictive, and the appended claims are intended to cover all suchmodifications, enhancements, and other embodiments that fall within thetrue scope of the claims. For example, the MCM was described herein inthe context of television receivers that receive both a satellite inputas a first type of input and a terrestrial/cable input as a second typeof input. In other embodiments, the receiver can support other types ofsignal sources. Moreover while the example above included twodemodulator die, the MCM can be expanded to three or more demodulatordie to support additional functions. Moreover other types of transportstreams can be supported besides the MPEG and GSE streams describedabove. Also a variety of package types such as BGA, micro-BGA, quadflat-pack (QFP), quad flat no-leads (QFN) and the like may be used forthe MCM.

Thus, to the maximum extent allowed by law, the scope of the presentinvention is to be determined by the broadest permissible interpretationof the following claims and their equivalents, and shall not berestricted or limited by the foregoing detailed description.

What is claimed is:
 1. A demodulator for a multi-mode receivercomprising: a demodulator die including: a first input port receiving asatellite input signal; a second input port receiving a terrestrial orcable input signal; a first transport stream port; a second transportstream port; a demodulator core responsive to an input from a selectedone of said first input port and said second input port for providing afirst transport stream signal to an output thereof; and a switchingcircuit responsive to a first mode for coupling said output of saiddemodulator core to a selected one of said first and second transportstream ports while keeping another one of said first and secondtransport stream ports in a high impedance state.
 2. The demodulator ofclaim 1 wherein: said multi-mode receiver comprises a televisionreceiver.
 3. The demodulator of claim 2 wherein: said first input portcomprises a satellite port and said second input port comprises aterrestrial/cable port.
 4. The demodulator of claim 1 wherein saidswitching circuit is further responsive to a second mode for couplingsaid first transport stream signal to both said first and secondtransport stream ports.
 5. The demodulator of claim 1 further wherein:said switching circuit further comprises a first readback buffer coupledto said first transport stream port and a second readback buffer coupledto said second transport stream port; and said demodulator core furthercomprises a collision detector for comparing readback data received froma selected one of said first and second readback buffers with said firsttransport stream signal, and detecting a collision in response to amismatch between said readback data and said first transport streamsignal.
 6. The demodulator of claim 5 wherein: said switching circuitfurther includes selectively enabled output buffers for buffering saidtransport stream signal; and said demodulator core further disables saidselectively enabled output buffers in response to detecting saidcollision.
 7. The demodulator of claim 1 wherein: said first input port,said second input port, said first transport stream port, said secondtransport stream port, said demodulator core, and said switching circuitare combined on a single demodulator die.
 8. The demodulator of claim 1wherein said demodulator core comprises: a configuration registeroperative to configure the switching circuit to couple said transportstream signal to said selected one of said first and second transportstream ports.
 9. The demodulator of claim 8 wherein said demodulatorcore comprises: a serial port coupled to said configuration register forreceiving at least one configuration bit from a serial input/output portand storing said at least one configuration bit in said configurationregister.
 10. The demodulator of claim 1 wherein each of said first andsecond transport stream ports comprise a plurality of terminalsconducting signals corresponding to signals of a Motion Picture ExpertsGroup (MPEG) transport stream.
 11. A method for use in a multi-modereceiver comprising: receiving a first input signal on a first inputport of a first demodulator die; receiving a second input signal on asecond input port of said first demodulator die; demodulating a selectedone of said first input signal and said second input signal to provide afirst demodulated output signal; switching said first demodulated outputsignal to a first transport stream port of said first demodulator diewhile keeping a second transport stream port in a high impedance statein response to a first mode of operation; and switching said firstdemodulated output signal to said second transport stream port of saidfirst demodulator die while keeping said first transport stream port ina high impedance state in response to a second mode of operation. 12.The method of claim 11 further comprising: switching said firstdemodulated output signal to both said first transport stream port andsaid second transport stream port in response to a third mode ofoperation.
 13. The method of claim 12 further comprising: receiving athird input signal on a first input port of a second demodulator die;receiving a fourth input signal on a second input port of said seconddemodulator die; demodulating a selected one of said third input signaland said fourth input signal to provide a second demodulated outputsignal; switching said second demodulated output signal to said secondtransport stream port in response to said first mode of operation;switching said second demodulated output signal to said first transportstream port in response to said second mode of operation; and switchingsaid demodulated output signal to neither of said first transport streamport or said second transport stream port in response to said third modeof operation.
 14. The method of claim 11 further comprising: receivingreadback data from one of said first transport stream port and saidsecond transport stream port; comparing said readback data withcorresponding outgoing data; and detecting a collision in response to amismatch between said readback data and said corresponding output data.15. The method of claim 11 further comprising: receiving readback datafrom said first transport stream port; combining said readback data withsaid first demodulated signal to form a bonded channel signal; andproviding said bonded channel signal to said second transport streamport.
 16. The method of claim 11 wherein: said receiving said firstinput signal on said first input port of said first demodulator diecomprises receiving said first input signal on a satellite port of saidfirst demodulator die; and said receiving said second input signal onsaid second input port of said first demodulator die comprises receivingsaid second input signal on a terrestrial/cable port of said firstdemodulator die.
 17. The method of claim 16 wherein: said switching saidfirst demodulated output signal to said first transport stream port inresponse to said first mode of operation comprises switching said firstdemodulated output signal to a first plurality of terminals conductingsignals corresponding to signals of a Motion Picture Experts Group(MPEG) transport stream; and said switching said first demodulatedoutput signal to said second transport stream port in response to saidsecond mode of operation comprises switching said first demodulatedoutput signal to a second plurality of terminals conducting signalscorresponding to signals of said MPEG transport stream.
 18. The methodof claim 11 further comprising: receiving at least one configuration bitand selecting said first mode and said second mode in response tocorresponding states of said at least one configuration bit.
 19. Themethod of claim 18 wherein said receiving said at least oneconfiguration bit comprises: receiving said at least one configurationbit from a serial input/output port.
 20. The method of claim 18 wherein:the method further comprises storing said at least one configuration bitin a configuration register.